1. Field of the Invention
The invention relates in general to an apparatus and a method for changing optical tweezers, and more particularly to an apparatus and a method using a mask element to change optical tweezers.
2. Description of the Related Art
The technology of laser optical tweezers has been developed and is now in use already. As the laser optical tweezers is a non-destructive tweezers, which controls particles without damaging them, the laser optical tweezers is now widely used in the fields such as micro-electro-mechanical system, bio-medicine, nano manufacturing process and so on.
The current mechanisms of using laser optical tweezers technology to control particle movement cause particles to generate linear, deflective or whir-pooled particle movement by adjusting the optical field intensity or changing the DOE pattern so as to change the gradient of the optical pressure received by the particles. However, the movement of the particles cannot be controlled without adjusting a laser beam modulator or adding an external source of momentum by ways of fluidic flow or static electricity.